Neurons Structure and Function Quiz

Questions and Answers

What are dendrites?

Dendrites receive nerve impulses from other neurons or sensory receptors and transmit the nerve impulses towards the cell body/soma of the neuron.

What is an axon?

An axon is an extension from the cell body that transmits the nerve impulses away from the cell body towards the synaptic bulbs.

Describe the structure of sensory neurons.

Sensory neurons have long dendrites and short axons.

What is the function of sensory neurons?

The function of sensory neurons is to receive information from sensory receptors and convert it to nerve impulses. Signup and view all the answers

What is the structure of relay neurons?

Relay neurons have short dendrites and short axons. Signup and view all the answers

What is the function of relay neurons?

Relay neurons are only found in the brain and spinal cord and they allow communication between sensory and motor neurons. Signup and view all the answers

Describe the structure of motor neurons.

Motor neurons have short dendrites and long axons. Signup and view all the answers

What is the function of motor neurons?

The function of motor neurons is to carry impulses from the CNS to effectors, such as muscles and glands. Signup and view all the answers

What does the strength of the muscle contraction depend on?

The strength of the muscle contraction depends on the rate at which the neurons fire action potentials. Signup and view all the answers

What causes muscle relaxation?

Muscle relaxation is caused by inhibition of motor neurons. Signup and view all the answers

Study Notes

Structure of Neurons

Dendrites: Receive nerve impulses from other neurons or sensory receptors and transmit them towards the neuron's cell body.
Axon: An extension from the cell body that transmits nerve impulses away from the cell body toward synaptic bulbs.
Sensory Neurons: Characterized by long dendrites and short axons, allowing them to quickly relay information from sensory receptors.
Relay Neurons: Have short dendrites and short axons, located in the brain and spinal cord, facilitating communication between sensory and motor neurons.
Motor Neurons: Feature short dendrites and long axons. They originate in the central nervous system (CNS) and extend into the peripheral nervous system (PNS) to stimulate muscles or glands.

Functions of Neurons

Sensory Neurons: Convert sensory information (e.g., pain, heat, visual input) into nerve impulses, transmitting them to the spinal cord and brain. In reflex actions, they communicate directly with the spinal cord to expedite responses.
Relay Neurons: Act as intermediaries between sensory and motor neurons, found exclusively within the brain and spinal cord.
Motor Neurons: Carry impulses from the CNS to effectors such as muscles and glands. They control muscle contractions by releasing neurotransmitters at synapses, which bind to muscle receptors, generating action potentials that lead to contraction.

Muscle Contraction and Relaxation

Strength of Contraction: Dependent on the firing rate of action potentials by neurons.
Muscle Relaxation: Occurs due to the inhibition of motor neurons, preventing muscle contractions.

Description

Test your understanding of sensory, relay, and motor neurons with our comprehensive flashcards. This quiz covers essential definitions and functions of key neuron components like dendrites and axons, helping you solidify your knowledge of neuroscience.